All sensations, movements, thoughts, memories, and feelings are the result of signals that pass through neurons. Neurons consist of three parts. The cell body 13 contains the nucleus, where most of the molecules that the neuron needs to survive and function are manufactured.
Dendrites 14 extend out from the cell body like the branches of a tree and receive messages from other nerve cells. Signals then pass from the dendrites through the cell body and may travel away from the cell body down an axon 15 to another neuron, a muscle cell, or cells in some other organ.
The neuron is usually surrounded by many support cells. Some types of cells wrap around the axon to form an insulating sheath This sheath can include a fatty molecule called myelin, which provides insulation for the axon and helps nerve signals travel faster and farther.
Or axons may be very long, such as those that carry messages from the brain all the way down the spinal cord. Scientists have learned a great deal about neurons by studying the synapse—the place where a signal passes from the neuron to another cell. When the signal reaches the end of the axon it stimulates the release of tiny sacs These sacs release chemicals known as neurotransmitters 18 into the synapse The neurotransmitters cross the synapse and attach to receptors 20 on the neighboring cell.
These receptors can change the properties of the receiving cell. If the receiving cell is also a neuron, the signal can continue the transmission to the next cell. Neurotransmitters are chemicals that brain cells use to talk to each other.
Some neurotransmitters make cells more active called excitatory while others block or dampen a cell's activity called inhibitory. Acetylcholine is an excitatory neurotransmitter because it generally makes cells more excitable. It governs muscle contractions and causes glands to secrete hormones.
Glutamate is a major excitatory neurotransmitter. Too much glutamate can kill or damage neurons and has been linked to disorders including Parkinson's disease, stroke, seizures, and increased sensitivity to pain. GABA gamma-aminobutyric acid is an inhibitory neurotransmitter that helps control muscle activity and is an important part of the visual system.
Serotonin is a neurotransmitter that constricts blood vessels and brings on sleep. It is also involved in temperature regulation. Low levels of serotonin may cause sleep problems and depression, while too much serotonin can lead to seizures. Dopamine is an inhibitory neurotransmitter involved in mood and the control of complex movements. Many medications used to treat behavioral disorders work by modifying the action of dopamine in the brain. The brain is one of the hardest working organs in the body.
When the brain is healthy it functions quickly and automatically. But when problems occur, the results can be devastating.
Some million Americans suffer from devastating brain disorders at some point in their lives. Knowing more about the brain can lead to the development of new treatments for diseases and disorders of the nervous system and improve many areas of human health. Most research funded by the NINDS is conducted by scientists in public and private institutions such as universities, medical schools, and hospitals.
Government scientists also conduct a wide array of neurological research in the more than 20 laboratories and branches of the NINDS itself. This research ranges from studies on the structure and function of single brain cells to tests of new diagnostic tools and treatments for those with neurological disorders. Mind maps allow for greater creativity when recording ideas and information whatever the topic, and enable the note-taker to associate words with visual representations.
Mind Mapping For Dummies explains how mind mapping works, why it's so successful, and the many ways it can be used. It takes you through the wide range of approaches to mind mapping, looks at the available mind mapping software options, and investigates advanced mind mapping techniques for a range of purposes, including studying for exams, improving memory, project management, and maximizing creativity.
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Crowdsourcing is an innovative way of outsourcing tasks, problems or requests to a group or community online. There are lots of ways business can use crowdsourcing to their advantage: be it crowdsourcing product ideas and development, design tasks, market research, testing, capturing or analyzing data, and even raising funds.
It offers access to a wide pool of talent and ideas, and is an exciting way to engage the public with your business. Crowdsourcing For Dummies is your plain-English guide to making crowdsourcing, crowdfunding and open innovation work for you.
It gives step-by-step advice on how to plan, start and manage a crowdsourcing project, where to crowdsource, how to find the perfect audience, how best to motivate your crowd, and tips for troubleshooting.
Written by two highly experienced leadership and coaching consultants, this book provides practical, hands-on instruction that can help you turn your meetings and training sessions around. Boost productivity by engaging attendees from the start, scheduling with time and energy levels in mind and keeping to a clear agenda. You'll learn the skills that will help you get the most out of every group session and discover which seemingly small details can have a huge impact on outcomes.
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